#8: Mario - Super Mario Bros. series
Princess Peach may be his trophy lady, but he's had other women in his life. Pauline was his first girlfriend when he made his debut in Donkey Kong but she only lasted one game (two if you count the remake), Goombella whom was only a one-time thing, Princess Daisy whom also seemed like a one-timer but started resurfacing in party games. Last but not least is Rosalia but that's only in fanfiction. It's a shame he could not be ranked higher.
Actually, Pauline was actually in a total of 3 games (if you count the remake). She was also in Mario vs. DK: March of the Minis, where she received a nice design revamp that made her quite hawt.
And, in my opinion, I doubt that Goombella and Rosalia were girls that Mario took that seriously (if at all). In both instances, he was focused on saving on saving his designated woman, which wouldn't really leave him with much time to have a "lil sumthin' on the side".

Yoshi
You might not think on the surface that Yoshi puts a lot of effort into this. But if he can tell a male Birdo from a female Birdo (we all hope; it's in Camelot's hands) then that pretty much puts him ahead of the entire human race so far as attention to detail goes. You can't tell me he was born like that, the little green guy has to have a few secret romps in his catalogue. I'm sure of it.
The American side of the equation may always make Birdo's gender questionable, vary from game to game, but in Japan, "Catherine" was ALWAYS a tranny. That much is inescapable.
In fact, if I remember correctly, Cathy's lil profile in the Japanese version of MK:DD was basically as follows:
"...Seems to be Yoshi's girlfriend....or should that be 'boyfriend'?...."

Princess Peach
Who says the player has to be a man? Seriously, how many guys has Peach been cockteasing? Mario, Booster, and HIGH TECHNICAAAL chameleons are only the tip of the iceberg. She keeps Yoshi satisfied despite making him sleep on the roof. And of course, her biggest victim is the big man himself, Bowser. There's something to be said for having a giant snapper turtle who rules over every other creature in the world wrapped around your finger. Too bad the poor guy usually winds up getting dunked in lava whenever he gets turned on.
*stands up and applauds* YES.
Peach HAS to be aware of what's she doing. She knows fully well that Mario and Bowser will be content to battle each other, until the end of time (or whenever Ninty gets tired of making Mario games, whichever comes first!)....and all because of her. Wouldn't be surprised if she and Bowser actually DID fool around a bit in between kidnapping episodes...after all, why didn't she just say something to the effect of "HELLLLLLLLLLLLL NAW!" to Jr, when he started popping off and claiming she was his "Mama", back in Sunshine?
She always has that whole "gentle and demure (and some what air-headed)" act going for her, but no no no...the whole rule of "players being able to spot game" demands that her game being recognized for what it is.
She's one of the most cunning and accomplished players in her field, and all the while, the fate of the entirety of the "Mario-verse" will always hang in the balance, as long as she wants it to. Nobody else can even hope to TOUCH her, in that respect.
Don't be fooled by those air-head-like remarks of "Peachy~!". Peach is one stone-cold, UTTERLY SMUG Q. Bee.